Rationale and Design of a Genetic Study on Cardiometabolic Risk Factors: Protocol for the Tehran Cardiometabolic Genetic Study (TCGS).

BACKGROUND: Cardiometabolic risk factors comprise cardiovascular diseases and/or diabetes, and need to be evaluated in different fields. OBJECTIVE: The primary aim of the Tehran Cardiometabolic Genetic Study (TCGS) is to create a comprehensive genome-wide database of at least 16,000 Tehranians, who are participants of the ongoing Tehran Lipid and Glucose Study (TLGS) cohort. METHODS: TCGS was designed in collaboration with the Research Institute for Endocrine Sciences and the genetic company deCODE. Participants had already been followed for over a 20-year period for major cardiometabolic-related health events including myocardial infarction, stroke, diabetes mellitus, hypertension, obesity, hyperlipidemia, and familial hypercholesterolemia. RESULTS: The TCGS cohort described here comprises 17,186 (86.3%) of the 19,905 TLGS participants who provided a baseline blood sample that was adequate for plasma and deoxyribonucleic acid analysis. This study is comprised of 849 individuals and 3109 families with at least one member having genotype information. Finally, 5977 males and 7422 females with the total genotyping rate of 0.9854 were genotyped with HumanOmniExpress-24-v1-0 bead chips (containing 649,932 single-nucleotide polymorphism loci with an average mean distance of 4 kilobases). CONCLUSIONS: Investigations conducted within the TCGS will seek to identify relevant patterns of genetic polymorphisms that could be related to cardiometabolic risk factors in participants from Tehran. By linking genome-wide data to the existing databank of TLGS participants, which includes comprehensive behavioral, biochemical, and clinical data on each participant since cohort inception in 1999, the TCGS will also allow exploration of gene-gene and gene-environment interactions as they relate to disease status.

CVD-predictive performances of "a body shape index" versus simple anthropometric measures: Tehran lipid and glucose study.

PURPOSE: To examine whether a body shape index (ABSI) calculated by using waist circumference (WC) adjusted for height and weight could improve the predictive performances for cardiovascular disease (CVD) of the Framingham's general CVD algorithm and to compare its predictive performances with other anthropometric measures. METHODS: We analyzed data on a 10-year population-based follow-up of 8,248 (4,471 women) individuals aged ≥30 years, free of CVD at baseline. CVD risk was estimated for a 1 SD increment in ABSI, body mass index (BMI), waist-to-hip ratio (WHpR) and waist-to-height ratio (WHtR), by incorporating them, one at a time, into multivariate accelerated failure time models. RESULTS: ABSI was associated with multivariate-adjusted increased risk of incident CVD among both men (1.26, 95% CI 1.09-1.46) and women (1.17, 1.03-1.32). Among men, for a one-SD increment, ABSI conferred a greater increase in the hazard of CVD [1.26 (1.09-1.46)] than did BMI [1.06 (0.94-1.20)], WC [1.15(1.03-1.28)], WHpR [1.02 (1.01-1.03)] and WHtR [1.16 (1.02-1.31)], and the corresponding figures among women were 1.17 (1.03-1.32), 1.02 (0.90-1.16), 1.11 (0.98-1.27), 1.03 (1.01-1.05) and 1.14 (0.99-1.03), respectively. ABSI as well as other anthropometric measures failed to add to the predictive ability of the Framingham general CVD algorithm either. CONCLUSIONS: Although ABSI could not improve the predictability of the Framingham algorithm, it provides more information than other traditional anthropometric measures in settings where information on traditional CVD risk factors are not available, and it can be used as a practical criterion to predict adiposity-related health risks in clinical assessments.

A cross sectional study on prevalence and etiology of syncope in Tehran.

Recurrent syncope of obscure etiology, particularly in those with structural heart diseases, is associated with higher mortality rates. There are insufficient and conflicting data on prevalence and etiology of syncope in the urban Middle Eastern population. Evaluating the etiologic basis of syncope can be an effective step in prevention of morbidities and sudden cardiac death in susceptible populations. The aim of our study was to determine the prevalence and etiology of syncope in an outpatient cardiology clinic in Tehran the capital of Iran. In this cross sectional study data was collected from patients' records whose first visits were from March 2006 to September 2007 and had undergone thorough examination for syncope (ECG, Holter monitoring, echocardiography, Tilt table testing, Electrophysiological study). All efforts were done to determine underlying heart diseases, physical exam and test abnormalities, final diagnosis and treatment in all selected patients. Overall prevalence of syncope was estimated to be 9%. The age-specific prevalence rates were 5-14 years:  4.14%, 15-44 years: 44.8%, 45-64 years: 31%, 65 years and Older: 20%. The most frequently identified cause (60%) was neurally-mediated (vasovagal) syncope. Mean age of patients was 44.9 years with a minimum of 5 years and maximum of 85 years. In our study, coronary heart disease had a high prevalence among participants (12.4%). Syncope is a common clinical problem. In this study prevalence rates peaked in 15-44 years age group. Considering that recurrent syncope is often disabling and may cause injury and the fact that heart diseases are more common in people affected by syncope, especial cautions should be taken while evaluating this group of patients.

Sudden cardiac death as a result of neglected hypopituitarism.

Cardiac involvement infrequently occurs in hypopituitarism, and lethal cardiac arrhythmias are rarely reported. We present a middle age female who died as a consequence of refractory ventricular arrhythmia whose medical history and previous laboratory investigation were consistent with hypopituitarism. We conclude that hypopituitarism may lead to electrocardiographic changes and malignant ventricular arrhythmia and should be included in laboratory investigation and differential diagnosis of patients presenting with long QT syndrome.

Value of exercise tolerance testing in evaluation of diabetic patients presented with atypical chest discomfort.

BACKGROUND: Coronary artery disease is the single most important cause of mortality and morbidity in diabetic patients. Electrocardiographic stress test is a non-invasive modality to screen significant coronary involvement in minimally symptomatic diabetics. OBJECTIVES: We investigated the Positive Predictive Value (PPV) of this test in comparison with coronary angiography. MATERIALS AND METHODS: 130 diabetic patients with atypical chest discomfort were studied and tested using Exercise Tolerance Test (ETT) among which 100 cases showed positive results that further were studied invasively by selective coronary angiography. RESULTS: The positive predictive value of ETT for diagnosis of Coronary Artery Disease (CAD)among diabetic patients presented with atypical chest discomfort was 77%. CONCLUSION: We conclude that electrocardiographic stress test is a valuable inexpensive non-invasive screening test in diabetic patients with atypical chest discomfort.

Prevalence of QTc interval changes in acute psychiatric care: a cross-sectional study.

INTRODUCTION: In a case series we examined the prevalence and incidence of QT changes during a 1-week interval in hospitalized patients in a general psychiatry ward during a 6-month period. METHOD: This cross-sectional study was done on electrocardiographic QT interval of patients admitted to the Psychiatric Department of Taleghani Hospital during a 6-month period excluding subjects with underlying cause of QT prolongation. RESULTS: Admission and follow-up electrocardiograms of 27 men and 47 women were studied, there was significant QT prolongation during hospitalization (P value 0.001) in approximately 30% of subjects, irrespective of type of administered medication. CONCLUSION: Pro-arrhythmic changes as reflected in QTc prolongation and QTc dispersion in electrocardiograms are common in patients admitted in psychiatric wards irrespective of type of therapy and should be screened and followed by serial electrocardiograms to minimize untoward cardiac outcomes.

Lipid profile components and incident cerebrovascular events versus coronary heart disease; the result of 9 years follow-up in Tehran Lipid and Glucose Study.

OBJECTIVE: To assess the effects of lipid component total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and non-HDL-C on risk of stroke events versus coronary heart disease (CHD). METHODS: The study was conducted on 2620 Iranians, aged ≥ 50 years, free from cardiovascular events at baseline (1999-2001). The multivariable hazard ratios (HRs) for stroke/CHD were calculated for 1 mmol/L change in lipid components, using Cox proportional hazard regression. RESULTS: During 9.1 years of follow-up, 73 and 358 cases of stroke and CHD occurred. We found significant interactions between TC and non-HDL-C with gender in risk prediction of stroke. Among women, multivariate adjusted HRs of ischemic stroke were 1.40 (1.08-1.82), 1.66 (0.71-3.86), 2.27 (0.58-8.91), 1.51 (1.06-2.15) and 1.36 (1.024-1.78) for TC, Ln TG, HDL-C, LDL-C and non-HDL-C respectively, while corresponding HRs of ischemic stroke for men were 0.78 (0.55-1.11), 0.71 (0.33-1.51), 1.04 (0.24-4.47), 0.82 (0.56-1.22), 0.78 (0.55-1.11), respectively. We found no interaction between gender and any of the lipids in risk prediction of incident CHD (p > 0.3). All lipid components were independently associated with CHD in whole population. CONCLUSION: The associations of lipid components on ischemic stroke were modified by gender. Only among female population, TC, LDL-C and non-HDL-C were independently associated with increased risk of ischemic stroke. Regarding CHD events, all lipid components were significant predictors.

Isolated post-challenge hyperglycaemia and risk of cardiovascular events: Tehran Lipid and Glucose Study.

OBJECTIVE: To evaluate the risk of cardiovascular events in diabetes defined by isolated post-challenge hyperglycaemia (IPH). METHODS: We followed 3794 subjects aged ≥40 years without known history of diabetes or cardiovascular disease (CVD) at baseline for CVD events. Participants were categorized as subjects without diabetes [fasting plasma glucose (FPG) < 126 mg/dL and 2-h post-challenge plasma glucose (2-hPG) < 200 mg/dL], IPH (FPG < 126 mg/dL and 2-h PG ≥ 200 mg/dL) and fasting hyperglycaemia (fasting blood glucose (FBS) ≥ 126 mg/dL). Hazard ratios (HRs) were calculated with the use of Cox proportional-hazards regression models to evaluate the risk of CVD events. RESULTS: At baseline, of 486 subjects with newly diagnosed diabetes, 190 (39%) had IPH. Over the next 8 years, age and sex-adjusted HR for incident CVD was 1.77 (95% confidence interval (CI): 1.19-2.64; p = 0.005) in subjects with IPH compared with subjects without diabetes. After further adjustment for potential confounders, the HR for CVD was not significant [1.32 (95% CI: 0.88-1.99; p = 0.2)]. CONCLUSIONS: IPH in middle-aged adults adds nothing for identifying CVD risks when other risk factors are taken into account. Associated metabolic risk factors seem to be more important than hyperglycaemia per se.

Adult height and risk of coronary heart disease: Tehran Lipid and Glucose Study.

BACKGROUND: We assessed the relationship between height and coronary heart disease (CHD) in an urban population of Tehran. METHODS: 4110 participants of the Tehran Lipid and Glucose Study who were 40 years of age or older (1880 men and 2230 women; mean age, 55.1 and 53.0 years, respectively) and free of CHD at baseline were followed for a mean of 9.1 years. We used Cox proportional hazards regression to evaluate the risk of a first CHD event across height tertiles. RESULTS: First CHD events occurred in 239 men and 172 women. The estimated crude HR (95% CI) for CHD events associated with an increment of 1 SD in height was 0.96 (0.28-3.33) in men and 0.84 (0.72-0.97) in women. After adjustment for age, the associations were no longer present. Further adjustment for other confounders had little impact on the results: the HR (95% CI) associated with an increase of 1 SD in height was 1.02 (0.87-1.20) in men and 0.82 (0.66-1.02) in women. CONCLUSIONS: After adjustment for age, height was not associated with CHD incidence in men or women.

Sudden cardiac death after treatment with low dose risperidone in combination with cotrimoxazole.

UNLABELLED: Risperidone as an antipsychotic drug raises the risk of serious ventricular tachyarrhythmias and sudden cardiac death; co-administered with other potentially arrhythmogenic drugs the risk escalates. There are some electrocardiographic markers which may help predict such events. CASE REPORT: We describe a 47-year-old woman with acute psychosis, who died suddenly subsequent to refractory ventricular arrhythmia, while on low dose risperidone combined with cotrimoxazole. CONCLUSION: This case report suggests that use of risperidone even at a low dose and in an apparently healthy individual is associated with a heightened risk of lethal ventricular tachyarrhythmia. Therefore, clinicians should always be aware of such awkward effect. It is recommended to obtain baseline electrocardiogram in all patients and follow up electrocardiograms in selected patients when considering such therapy in order to avoid fatal outcomes.

Association of educational status with cardiovascular disease: Teheran Lipid and Glucose Study.

OBJECTIVE: The aim of this study was to evaluate the associations between educational level and cardiovascular disease (CVD) in an older Iranian population. METHODS: To estimate the odds ratio (OR) of educational level in a cross-sectional study, logistic regression analysis was used on 1,788 men and 2,204 women (222 men and 204 women positive based on their CVD status) aged ≥ 45 years. RESULTS: In men, educational levels of college degree and literacy level below diploma were inversely associated with CVD in the multivariate model [0.52 (0.28-0.94), 0.61 (0.40-0.92), respectively], but diploma level did not show any significant association with CVD, neither in the crude model nor in the multivariate model. In women, increase in educational level was inversely associated with risk of CVD in the crude model, but in the multivariate adjusted model, literacy level below diploma decreased risk of CVD by 39%, compared with illiteracy. CONCLUSION: Our findings support those of developed countries that, along with other CVD risk factors, educational status has an inverse association with CVD among a representative Iranian population of older men and women.